In the case of electronic subassemblies used for safety purposes, for example, in automotive and aerospace applications, it has proven worthwhile to test the subassemblies themselves, as well as each individual component of the subassembly, and to record the manufacturing and test steps using process cards. On the one hand, these records help to insure a manufacturing method which is free of errors, and consequently products, which are free of defects; on the other hand, the test reports make error analyses possible, in case errors should occur later on. Evidently, these strict manufacturing and test specifications are extremely expensive and time-consuming and make the product itself more expensive. In addition, the test documents accompanying the product, in the case of complex subassemblies, are very voluminous and require considerable storage space and administrative work on the part of the manufacturer and user of the subassembly.
Furthermore, it is a known procedure from the periodical "Feinwerktechnik und Messtechnik" (Precision Engineering and Metrology) 96 (1988) 5, pages 209 and 210, to test automatically electronic subassemblies for automotive electronics on computer controlled test stands and to transmit the test results through a network to a master computer, which files these test results in a data bank system for repair purposes.